Out of 29 WT mice infected with HSV-CD80 virus, 24 mice survived (83%); 24 out of 28 (86%) WT mice infected with dLAT2903 virus survived ocular infection; similarly, 24 out of 27 (89%) CD80-/- mice infected with HSV-CD80 virus survived; and 24 out of 25 (96%) CD80-/- mice infected with dLAT2903 virus survived ocular infection. This evidence concerns the gene CD80 and eye infection.